Random pops and crackling in sound with USB DAC

Help and Support Raspberry Pi
1

Hello,
I have a problem with the sound of my USB DAC, the steinberg ur22. The device is recognized by alsa and I can choose it in the audio settings. But if I play a movie or music file, there are random pops every few seconds, just like dirt on vinyl. The DAC needs 500mA power, my power supply has 2A. I tried to set the USB current to the Maximum with the command in the pi config.txt, but this changes nothing. To be sure, that there is no problem with the power consumption, I will try to power the DAC with an own source later. I don’t know what I should do now, I tried also different options in the asound.conf and asoundrc config files, but I think they are being ignored. I commented the index in the alises of the usb snd device, so that the card number is 0 and blacklisted the snd_bcm2835. I also tried some things with different options in the cmd line, such as dwc_otg.fiq_split_enable=0 or tried options snd-usb-audio nrpacks=1 in the alsa conf file. But nothing helped.

Greetings
Jens

2

I added an external power source, but nothing improved, I added a few lines in the /boot/config.txt

audio_pwm_mode=2
disable_pvt=1
force_turbo=1
audio_pwm_mode=2
audio_sdm_mod_order=2
disable_audio_dither=1

If I try to create an asound.conf or .asoundrc file and try to set the UR22 (card1) as an default device, my settings in the asound are still ignored by kodi. The default device is bcm2835. It’s the proof, that nothing in the asoundconf changes the behaviour of kodi sound system.